User manual B&W DS6

[. . . ] the DS6 incorporates a woven Kevlar® cone bass/midrange drive unit for lowest coloration and maximum definition. It also has two paper midrange/highfrequency units to ensure dipolar dispersion and maintain dynamics to high sound levels. Kevlar® cones were originally developed for the acclaimed B&W 800 Series systems and go towards the realisation of fine transducers. [. . . ] NOTE: Certain power amplifiers cause a polarity reversal between input and output. Ensure the polarity convention for all the amplifiers you use is consistent, if ill-defined sound panning and strange phase and frequency effects are to be avoided. These surround speakers conform to the specifications of Lucasfilm's Home THX audio system and differ from most conventional speakers in that they have a dipolar radiation pattern. The sound is projected mainly backwards and forwards - with drive units mounted on opposite sides of the cabinet. sound radiated in one direction has the reverse polarity to that radiated in the opposite direction. In a plane at right angles to these two lobes, the sound is substantially cancelled out. The speakers are used with the null plane directed towards the listeners, who therefore hear very little direct sound. Most of the sound they hear has been reflected off the surfaces of the room and is diffuse in nature. This gives the enveloping and atmospheric sound field that is necessary for good Home THX and Dolby Pro Logic reproduction. The speakers should ideally be mounted on or close to the side (walls of the room and in line with the centre row of listeners. 5m (20in) from the ceiling and over 1m (40in) clear of the rear walls. For the best atmospheric effect mount the speakers above the head of the listeners. As with all speakers some experimentation will reward the listeners with the optimum performance. a "Keyhole" mounting slot is provided in the rear baffle of the DS6 to facilitate wall mounting. A shelf stand is also provided where wall mounting would prove difficult. NOTE: The DS6 produces a static magnetic field that extends outside the cabinet boundary. [. . . ] Before attempting to decorate the cabinet, you should protect both the grille and the drive units. This can be effectively achieved by removing the grille, enclosing it in a plastic bag and refitting it so that the bag is held tightly in place all around the grille and drive unit area. If you wish to use an aerosol cleaner, remove the grille first by gently pulling it away from the cabinet. [. . . ]